[go: up one dir, main page]

SI1375684T2 - Process for the manufacture of bearing rings for large rolling bearings - Google Patents

Process for the manufacture of bearing rings for large rolling bearings

Info

Publication number
SI1375684T2
SI1375684T2 SI200331373T SI200331373T SI1375684T2 SI 1375684 T2 SI1375684 T2 SI 1375684T2 SI 200331373 T SI200331373 T SI 200331373T SI 200331373 T SI200331373 T SI 200331373T SI 1375684 T2 SI1375684 T2 SI 1375684T2
Authority
SI
Slovenia
Prior art keywords
race
manufacture
rolling bearings
bearing rings
large rolling
Prior art date
Application number
SI200331373T
Other languages
Slovenian (sl)
Other versions
SI1375684T1 (en
Inventor
Josef Bracht
Jorg Dr.-Ing. Rollmann
Bernd Stakemeier
Johannes Dr.-Ing. Wozniak
Original Assignee
Rothe Erde Gmbh
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Family has litigation
First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=27771553&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=SI1375684(T2) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by Rothe Erde Gmbh filed Critical Rothe Erde Gmbh
Publication of SI1375684T1 publication Critical patent/SI1375684T1/en
Publication of SI1375684T2 publication Critical patent/SI1375684T2/en

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C19/00—Bearings with rolling contact, for exclusively rotary movement
    • F16C19/22—Bearings with rolling contact, for exclusively rotary movement with bearing rollers essentially of the same size in one or more circular rows, e.g. needle bearings
    • F16C19/34—Bearings with rolling contact, for exclusively rotary movement with bearing rollers essentially of the same size in one or more circular rows, e.g. needle bearings for both radial and axial load
    • F16C19/38—Bearings with rolling contact, for exclusively rotary movement with bearing rollers essentially of the same size in one or more circular rows, e.g. needle bearings for both radial and axial load with two or more rows of rollers
    • F16C19/381—Bearings with rolling contact, for exclusively rotary movement with bearing rollers essentially of the same size in one or more circular rows, e.g. needle bearings for both radial and axial load with two or more rows of rollers with at least one row for radial load in combination with at least one row for axial load
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C19/00—Bearings with rolling contact, for exclusively rotary movement
    • F16C19/22—Bearings with rolling contact, for exclusively rotary movement with bearing rollers essentially of the same size in one or more circular rows, e.g. needle bearings
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/06—Surface hardening
    • C21D1/09—Surface hardening by direct application of electrical or wave energy; by particle radiation
    • C21D1/10—Surface hardening by direct application of electrical or wave energy; by particle radiation by electric induction
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/40—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for rings; for bearing races
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C33/00—Parts of bearings; Special methods for making bearings or parts thereof
    • F16C33/30—Parts of ball or roller bearings
    • F16C33/58—Raceways; Race rings
    • F16C33/64—Special methods of manufacture
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C2300/00—Application independent of particular apparatuses
    • F16C2300/10—Application independent of particular apparatuses related to size
    • F16C2300/14—Large applications, e.g. bearings having an inner diameter exceeding 500 mm
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P10/00—Technologies related to metal processing
    • Y02P10/25—Process efficiency
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/49—Method of mechanical manufacture
    • Y10T29/49636—Process for making bearing or component thereof
    • Y10T29/49643—Rotary bearing
    • Y10T29/49679—Anti-friction bearing or component thereof
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/49—Method of mechanical manufacture
    • Y10T29/49636—Process for making bearing or component thereof
    • Y10T29/49643—Rotary bearing
    • Y10T29/49679—Anti-friction bearing or component thereof
    • Y10T29/49682—Assembling of race and rolling anti-friction members
    • Y10T29/49684—Assembling of race and rolling anti-friction members with race making
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/49—Method of mechanical manufacture
    • Y10T29/49636—Process for making bearing or component thereof
    • Y10T29/49643—Rotary bearing
    • Y10T29/49679—Anti-friction bearing or component thereof
    • Y10T29/49689—Race making
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/49—Method of mechanical manufacture
    • Y10T29/49636—Process for making bearing or component thereof
    • Y10T29/49707—Bearing surface treatment

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Thermal Sciences (AREA)
  • Physics & Mathematics (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Rolling Contact Bearings (AREA)
  • Heat Treatment Of Articles (AREA)

Abstract

In producing a bearing ring for large roller bearing, in which race rim zone is hardened by heating with electromagnetic field of inductor(s) whilst rotating ring about its axis, then chilling, the distance of inductor from rim surface is: 1-2 times depth (T) to be hardened for radial race; 0.6-2 x T and 1.5-2 x T for outer and inner rims of axial race bounded by inner ring surface; and 0.6-1 x T for axial race with inside diameter greater than that of inner ring surface.
SI200331373T 2002-06-26 2003-04-19 Process for the manufacture of bearing rings for large rolling bearings SI1375684T2 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE10228333A DE10228333C1 (en) 2002-06-26 2002-06-26 Hardening the race rim zone in production of bearing ring for large roller bearing involves heating with inductor at specified distance whilst rotating ring about axis, and then chilling
EP03009096.3A EP1375684B2 (en) 2002-06-26 2003-04-19 Process for the manufacture of bearing rings for large rolling bearings

Publications (2)

Publication Number Publication Date
SI1375684T1 SI1375684T1 (en) 2008-12-31
SI1375684T2 true SI1375684T2 (en) 2014-02-28

Family

ID=27771553

Family Applications (1)

Application Number Title Priority Date Filing Date
SI200331373T SI1375684T2 (en) 2002-06-26 2003-04-19 Process for the manufacture of bearing rings for large rolling bearings

Country Status (8)

Country Link
US (1) US7146735B2 (en)
EP (1) EP1375684B2 (en)
JP (1) JP4603779B2 (en)
KR (1) KR101310702B1 (en)
AT (1) ATE408714T1 (en)
DE (2) DE10228333C1 (en)
ES (1) ES2311655T5 (en)
SI (1) SI1375684T2 (en)

Families Citing this family (26)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE525426C2 (en) * 2002-05-02 2005-02-15 Skf Ab Method of making rings and apparatus for carrying out the method.
DE10228333C1 (en) 2002-06-26 2003-09-25 Rothe Erde Gmbh Hardening the race rim zone in production of bearing ring for large roller bearing involves heating with inductor at specified distance whilst rotating ring about axis, and then chilling
DE112004001206B4 (en) * 2004-09-10 2015-08-20 Gkn Driveline International Gmbh Tempered joint cage
DE102005006701B3 (en) 2005-02-15 2006-03-30 Rothe Erde Gmbh Production of bearing ring for large rolling bearing comprises arranging inductors over common zone of annular track to be hardened, heating the opposite-lying edge layer to the hardening temperature and further processing
JP4811006B2 (en) * 2005-12-09 2011-11-09 日産自動車株式会社 Induction heat treatment method and induction heat treatment apparatus
DE202007002609U1 (en) * 2007-02-19 2008-04-03 Landwehr, Markus rotary joint
DE102007049087A1 (en) * 2007-10-12 2009-04-23 Rothe Erde Gmbh Radially and axially loadable rolling bearing
US8859084B2 (en) * 2008-01-29 2014-10-14 Fina Technology, Inc. Modifiers for oriented polypropylene
EP2605613A3 (en) * 2008-04-11 2014-07-23 The Timken Company Inductive heating using magnets for hardening of gear teeth and components alike
DK3228889T3 (en) * 2009-05-06 2023-02-27 Skf Ab RACING ELEMENT FOR A LARGE ROLLER BEARING AND BEARING ARRANGEMENT
WO2011010664A1 (en) * 2009-07-22 2011-01-27 Ntn株式会社 Method for heat-treating a ring-shaped member, method for producing a ring-shaped member, ring-shaped member, bearing ring, rolling bearing, and method for producing a bearing ring
JP5773348B2 (en) * 2009-12-01 2015-09-02 Ntn株式会社 Method of manufacturing bearing ring, bearing ring and rolling bearing
JP5773349B2 (en) * 2009-12-01 2015-09-02 Ntn株式会社 Method of manufacturing bearing ring and rolling bearing
JP5557235B2 (en) * 2009-07-22 2014-07-23 Ｎｔｎ株式会社 Heat treatment method for ring-shaped member, method for manufacturing ring-shaped member
KR101370568B1 (en) 2009-07-30 2014-03-06 고오슈우하네쓰렌 가부시기가이샤 Induction heating and quenching device, induction heating and quenching method, induction heating coil, heat treatment device, and heat treatment method
US8993942B2 (en) 2010-10-11 2015-03-31 The Timken Company Apparatus for induction hardening
JP5665565B2 (en) * 2011-01-21 2015-02-04 Ntn株式会社 Manufacturing method of bearing ring
CN103314119B (en) * 2011-01-21 2015-09-02 Ntn株式会社 The manufacture method of lasso, lasso and rolling bearing
JP5665564B2 (en) * 2011-01-21 2015-02-04 Ntn株式会社 Manufacturing method of bearing ring
DE102011122145A1 (en) * 2011-12-22 2013-06-27 Imo Holding Gmbh Rolling element assembly useful for rotational connection with ball-rolling element raceway system, comprises overlap region at initial- and end region of hardened rolling body raceway, where overlap region has region of lesser hardness
DE102014206428A1 (en) * 2014-04-03 2015-10-08 Schaeffler Technologies AG & Co. KG Method for producing a rolling bearing and rolling bearing
JP2017082945A (en) * 2015-10-29 2017-05-18 Ntn株式会社 Double row tapered roller bearing, race ring and method of manufacturing double row tapered roller bearing
EP3364061A1 (en) 2017-02-20 2018-08-22 Flender GmbH Usage of an induction hardened bearing
DE102017216762A1 (en) 2017-09-21 2019-03-21 Thyssenkrupp Ag Material and manufacturing process for rolling bearing components
DE102018212775A1 (en) 2018-07-31 2020-02-06 Aktiebolaget Skf bearing ring
DE102019201999A1 (en) * 2019-02-14 2020-08-20 Thyssenkrupp Ag Device and method for inductive shot hardening of roller bearing raceways

Family Cites Families (28)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2145864A (en) * 1934-07-12 1939-02-07 Ohio Crankshaft Co Method of making hardened surface articles
US2288033A (en) * 1936-09-22 1942-06-30 Budd Induction Heating Inc Method of producing autofrettaged hubs
US2419691A (en) * 1943-12-23 1947-04-29 Julius E Shafer Bearing assembly
US3108913A (en) * 1961-03-16 1963-10-29 Ohio Crankshaft Co Crankshafts and method of hardening same
US3305409A (en) * 1962-12-26 1967-02-21 Int Harvester Co Heat process for crankshafts
DE1879514U (en) * 1963-06-14 1963-09-19 Eisenwerk Rothe Erde G M B H WIRE ROLL BEARING.
US3623128A (en) * 1968-02-02 1971-11-23 Aeg Elotherm Gmbh Apparatus for improving the torsional fatigue strength of crankshafts
DE2011141A1 (en) * 1970-03-10 1971-09-23 Jaeger Gmbh G & J Multi-row rolling bearing rotary connection with drive toothing
US3909314A (en) * 1973-11-02 1975-09-30 Park Ohio Industries Inc Method for inductively heating and quench hardening surfaces on a crankshaft
US3944446A (en) * 1975-05-22 1976-03-16 Park-Ohio Industries, Inc. Method of inductively heating and quench hardening camshafts
JPS52127417A (en) * 1976-04-19 1977-10-26 Koyo Seiko Co Ball races of balllbearing
DE2734916C3 (en) * 1977-08-03 1981-10-22 Estel Hoesch Werke Ag, 4600 Dortmund Inductor for heating raceway surfaces on roller bearing rings
JPS59177825U (en) * 1983-05-16 1984-11-28 光洋精工株式会社 Composite cylindrical roller bearing
US4599502A (en) * 1983-11-22 1986-07-08 National Forge Company Induction hardening of steel
JPS60141827A (en) * 1983-12-28 1985-07-26 Denki Kogyo Kk High frequency induction heating method
JPS641944Y2 (en) * 1984-10-31 1989-01-18
DE3623119C1 (en) * 1986-07-09 1987-05-27 Thyssen Ind Ag Schmiedetechnik Process for the inductive hardening of cylindrical bearing points with transition radii relieved with respect to the adjoining shaft parts and apparatus for carrying out the process
US4759808A (en) * 1986-12-22 1988-07-26 Tocco, Inc. Method for hardening cam lobes on a camshaft
DE4013148C1 (en) * 1990-04-25 1991-10-31 Mercedes-Benz Aktiengesellschaft, 7000 Stuttgart, De
US5451749A (en) * 1993-12-27 1995-09-19 Tocco, Inc. Inductor for inductively heating crank shafts
JP3580891B2 (en) † 1995-03-28 2004-10-27 Ｎｔｎ株式会社 Machining method for axle bearing outer ring
DE19610416A1 (en) * 1996-03-16 1997-09-18 Kessler Kg Maschf Method and device for inductive surface hardening of workpieces
JP3403329B2 (en) * 1997-12-26 2003-05-06 富士電子工業株式会社 High frequency heating coil for cylindrical workpiece
US6287009B1 (en) † 1998-03-06 2001-09-11 Nsk Ltd. Rolling bearing unit with rotation speed detection instrument for use in cars and method for working outer race for use in this bearing unit
JP2000154828A (en) * 1998-11-19 2000-06-06 Nippon Steel Corp Outer ring for constant velocity joint having excellent flaking resistance and shaft strength and method of manufacturing the same
JP2002174251A (en) * 2000-12-04 2002-06-21 Nsk Ltd Rolling bearing
JP3548523B2 (en) * 2000-12-15 2004-07-28 電気興業株式会社 High frequency induction heating coil
DE10228333C1 (en) 2002-06-26 2003-09-25 Rothe Erde Gmbh Hardening the race rim zone in production of bearing ring for large roller bearing involves heating with inductor at specified distance whilst rotating ring about axis, and then chilling

Also Published As

Publication number Publication date
ES2311655T5 (en) 2014-02-17
EP1375684B2 (en) 2013-10-23
EP1375684A2 (en) 2004-01-02
ES2311655T3 (en) 2009-02-16
ATE408714T1 (en) 2008-10-15
SI1375684T1 (en) 2008-12-31
EP1375684A3 (en) 2005-02-16
US7146735B2 (en) 2006-12-12
EP1375684B1 (en) 2008-09-17
DE10228333C1 (en) 2003-09-25
KR20040002692A (en) 2004-01-07
DE50310494D1 (en) 2008-10-30
KR101310702B1 (en) 2013-09-25
US20040000053A1 (en) 2004-01-01
JP2004044802A (en) 2004-02-12
JP4603779B2 (en) 2010-12-22

Similar Documents

Publication Publication Date Title
SI1375684T2 (en) Process for the manufacture of bearing rings for large rolling bearings
EP2050583A4 (en) ROLLER BEARING ELEMENT FOR BEARING UNIT, BEARING UNIT AND METHOD AND DEVICE FOR PRODUCING ROLLING BEARING BEARING ELEMENT FOR BEARING UNIT
EP2987873A3 (en) Method for heat-treating a ring-shaped member, method for producing a ring-shaped member, ring-shaped member, bearing ring, rolling bearing, and method for producing a bearing ring
WO2009078337A1 (en) Double-row angular bearing, bearing device for wheel, method of producing outer ring, and method of producing inner ring
BR9811822A (en) Process for the manufacture of steel rings for rolling bearings
JP2012183563A (en) Method of manufacturing shaft member for wheel rolling bearing device
CN107414425A (en) Wind-powered electricity generation gear ring bearing seamless ring technique
RU2012117599A (en) OIL FILM BEARING INSERT
JP2011117016A5 (en)
ATE462022T1 (en) RADIAL ROLLER BEARINGS, ESPECIALLY CYLINDER OR NEEDLE ROLLER BEARINGS, WITH HOLLOW ROLLERS MADE OF A SHAPE MEMORY ALLOY AS SPACER BODY
JP2006009891A5 (en)
JP2011117487A (en) Orbital ring and rolling bearing
JP2012197070A (en) Manufacturing method for wheel rolling bearing device, and wheel rolling bearing device
JP2011026633A (en) Method for heat-treating ring-shaped member, method for producing ring-shaped member, ring-shaped member, orbital ring of rolling bearing, and rolling bearing
JP2008169941A (en) Wheel bearing device
WO2017203915A1 (en) Heat treatment method for ring-shaped member, manufacturing method for ring-shaped member, bearing ring of roller bearing, and roller bearing
JP2009203525A (en) Production line for rolling bearing
KR20130053814A (en) The manufacturing method for bearing race
JP5644881B2 (en) Manufacturing method of wheel bearing rolling bearing device
JP2017082824A (en) Manufacturing method of outer ring of rolling bearing unit for wheel support
JP7122820B2 (en) machine parts
JP2014095154A (en) Heat treatment method for ring-shaped member, method for producing ring-shaped member, ring-shaped member, bearing ring of rolling bearing, and rolling bearing
CN201747776U (en) Cracking-type radial spherical plain bearing unit
CN208831509U (en) A wheel hub unit that is convenient for turning
JP2008266667A (en) Rolling bearing device for supporting wheel